Novel self balancing single phase 7 level inverter with coupled inductors

Abstract

This paper proposes a novel self balancing 7 level inverter with two coupled inductors. The proposed inverter can generate 7 levels with only one DC source. By series charging and parallel discharging of capacitors, it can self balance the voltage across the two capacitors. The proposed topology incurs a lower part count compared to existing (conventional) topologies and can self balance the voltage across capacitors without any extra balancing circuit with simple control strategy. Because of high frequency coupled inductors, the dead band between some of the power switches can be eliminated and output voltage distortion is low. A 1200W power rating system has been simulated to verify the viability of the proposed topology and the relevant simulation waveforms are included.